NestJS

Integrate Chimpbase into a NestJS application.

Chimpbase integrates with NestJS by wrapping your action logic in injectable services and wiring them into the Chimpbase registration system.

Setup

bun add @nestjs/core @nestjs/common

Define services

Wrap your action handlers in NestJS injectable services:

import { Injectable } from "@nestjs/common";
import type { ChimpbaseContext } from "@chimpbase/runtime";

@Injectable()
export class TodoService {
  async listTodos(ctx: ChimpbaseContext, filters: { projectId: number }) {
    return ctx.query("select * from todos where project_id = ?1", [filters.projectId]);
  }

  async createTodo(ctx: ChimpbaseContext, input: { title: string; projectId: number }) {
    const [todo] = await ctx.query<{ id: number }>(
      "insert into todos (title, project_id) values (?1, ?2) returning id",
      [input.title, input.projectId],
    );
    return todo;
  }
}

Create the NestJS module

import { Module } from "@nestjs/common";
import { TodoService } from "./todo.service.ts";

@Module({
  providers: [TodoService],
  exports: [TodoService],
})
export class TodoModule {}

@Module({
  imports: [TodoModule],
})
export class AppModule {}

Wire into Chimpbase

Bootstrap NestJS, pull out your services, and register them as Chimpbase actions:

import { NestFactory } from "@nestjs/core";
import { defineChimpbaseApp } from "@chimpbase/bun";
import { action } from "@chimpbase/runtime";
import { Hono } from "hono";
import type { ChimpbaseRouteEnv } from "@chimpbase/runtime";
import { AppModule } from "./src/nest/app.module.ts";
import { TodoService } from "./src/modules/todos/todo.service.ts";

const nestApp = await NestFactory.createApplicationContext(AppModule);
const todoService = nestApp.get(TodoService);

const app = new Hono<{ Bindings: ChimpbaseRouteEnv }>();

app.get("/todos", async (c) => {
  const todos = await c.env.action("listTodos", { projectId: 1 });
  return c.json(todos);
});

export default defineChimpbaseApp({
  project: { name: "my-app" },
  httpHandler: app.fetch,
  registrations: [
    action("listTodos", todoService.listTodos.bind(todoService)),
    action("createTodo", todoService.createTodo.bind(todoService)),
  ],
});

When to use NestJS

NestJS is useful when you need its dependency injection system for organising large codebases. For simpler projects, plain functions with defineChimpbaseApp are often enough.

Hono
Use Hono as your HTTP framework with Chimpbase.
Express
Use Express as your HTTP framework with Chimpbase.